Have you had experience working with shadow properties in object-oriented programming or ORM systems?

In the context of ORM systems and object-oriented programming, shadow properties are properties that are not explicitly declared in the model class but are stored and managed by the ORM itself. They are used to store additional information, such as foreign keys or auxiliary data that are not needed in business logic but are necessary for working with the database.

For example, in Entity Framework Core, you can define a shadow property that is not mapped to the class but exists in the data model:

modelBuilder.Entity<Order>()
    .Property<int>("ShadowProperty")
    .HasDefaultValue(0);

This allows storing data without cluttering the model and using it for internal ORM needs, such as tracking changes or relationships between entities.